JPEG-XL covers in media files

Has anyone tried to embed JPEG XL images in MP3s and MP4s yet, perhaps even successfully?

I haven’t and I suppose Mp3tag doesn’t support it in any container format, therefore I’m posting in the OT category.

Could you please provide such a JPEG XL image to reproduce it?

I wonder what a success would be:
Get only the data into the file?
Then display the picture?

As the ID3 standard talsk about png and jpg formats, I doubt that anything beside these 2 formats will lead to a successful display of the picture. Developers would have had to implement the xl codec in advance - which I doubt anybody has.
But perhaps there is someone out there. To find that out is what gathered to be the purpose of this thread.

I guess “success” is two-fold:

  • Editing software, like Mp3tag, accepts .jxl files to embed inside .mp3, .mp4 etc.
    • … using them verbatim.
    • … converting them on the fly to JPEG or PNG.
  • Playback and management software displays JPEG XL images embedded into audio or video files.

Writing this on my phone, I don’t have sample files at hand. Surprisingly, I did not find an online test suite of JXL utilizing different features of the new format, e.g. lossless JPEG transcoding, animation or transparency.
PS: Try this:

In the future, where enough playback software supports JXL, I’d also expect there to be an “optimize embedded pictures” tool that transcodes embedded JPEGs and PNGs to JPEG XL. This may or may not be an integral part of Mp3tag.

For me, intuitively, WebP is strongly related to MKV, because WebM is a derivative of the latter, while being ISO standards, JPEG and PNG (and JPEG XL) are closer to MPEG. However, that’s really nonsense.

Then there is HEIF (with HEIC, AVCF and AVIF), which are (photographic) image formats based upon the same ISOBMMF container as MP4s. I wouldn’t expect to use those for images embedded within audio or video (MPEG) files. However, I would assume that Mp3tag could be extended to support tagging of such files with relatively little effort. (This may well be me being naive.)